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.Dd September 10, 2013
.Dt HYPER-V 4
.Os
.Sh NAME
.Nm hv_utils
.Nd Hyper-V Utilities Driver
.Sh SYNOPSIS
To compile this driver into the kernel, place the following lines in
the system kernel configuration file:
.Bd -ragged -offset indent
.Cd "device hyperv"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides time keeping, shutdown and heartbeat
functionality for
.Fx
guest partitions running on Hyper-V.
Hyper-V is a hypervisor-based virtualization technology from Microsoft.
The
.Nm
driver is one of the core drivers required to be present in guest
partitions running on Hyper-V.
This driver provides the following
functionalities to guest partitions:
.Pp
(a) Time Keeping: The clock inside the guest partition will remain accurate by
synchronizing to the clock on the virtualization server via Timesync service,
and with the help of the pluggable time source device.
.Pp
(b) Integrated shutdown: Guest partitions running
.Fx
can be shut down from
Hyper-V Manager console by using the
.Qq Shut down
command.
.Pp
(c) Heartbeat: This feature allows the virtualization server to detect whether
the guest partition is running and responsive.
.Sh SEE ALSO
.Xr hv_ata_pci_disengage 4 ,
.Xr hv_netvsc 4 ,
.Xr hv_storvsc 4 ,
.Xr hv_vmbus 4
.Sh HISTORY
Support for
.Nm
first appeared in
.Fx 10.0 .
The driver was developed through a joint effort between Citrix Incorporated,
Microsoft Corporation, and Network Appliance Incorporated.
.Sh AUTHORS
.An -nosplit
.Fx
support for
.Nm
was first added by
.An Microsoft BSD Integration Services Team Aq Mt bsdic@microsoft.com .
